Solar energy, one of oldest and most frequently employed forms of green power, has tremendous untapped potential.  Some 86,000 terawatts of it reach the surface of the Earth each year, and in a broader sense provide human beings with a tremendous number of needs, from driving the photosynthesis that grows plants, to heating the planet, to creating regular weather patterns.  

On a more direct level, photovoltaic cells have been capturing rays of light and turning them into electricity for decades. While pollution-free and essentially inexhaustible, historically, the use of solar power for electricity has many significant drawbacks. Capital costs of building new infrastructure tend to be high, especially compared to other methods of power generation, and wide-scale solar power generation usually needs to happen in open, sunny areas.  

Generally, solar generation facilities end up being constructed in areas far from cities, which puts them furthest from where power is in highest demand. Most inconveniently of all, however, solar power traditionally required large flat surfaces to collect sunlight, making it impractical for smaller or more oddly shaped devices.  

Fortunately, recent developments in thin-film photovoltaic cells are gradually overcoming this shortfall.  Perhaps best known as the slender brown strip on low-end calculators, thin-film photovoltaic cells have in the past been unable to generate the necessary power to run more complex devices.  But recent developments and new technologies, such as cadmium-tellurium (CdTe) and copper-indium-selenium (CIS and CIGS) cells have allowed thinner, more flexible strips to reach energy conversion efficiencies—that is, the amount of energy that is converted to electricity—that rival traditional, non-thin strip photovoltaic cells.  

Aside from appealing to a wide variety of industries and devices (Apple recently filed a thin-film photovoltaic patent), the slender, flexible nature of the thin-cell product allows production methods such as roll-to-roll or printing that were infeasible with previous solar cell technologies. These methods could drastically increase production volumes of thin-film photovoltaics, while dramatically reducing the costs of manufacture. 

Perhaps most importantly of all, though, thin-film photovoltaics have a shorter energy payback time—that is, the amount of time it takes them to produce the energy expended in their construction—than their conventional solar counterparts.  That means, in a country that derives half of its energy from coal power, less carbon to compensate for, and more energy delivered without contributing to the global warming process.  

While there are some important cautions regarding thin-cell photovoltaics, such as the handling and disposal of the cadmium involved in some constructions, the sky seems to the be the limit for this burgeoning solar power implementation. Everything from clothes, to emergency battery chargers, to the military and space programs could benefit tremendously from this advancing, nearly carbon free-power source.

Photo courtesy of Got Solar